U.S. patent application number 12/123515 was filed with the patent office on 2009-11-26 for production of fuel materials utilizing waste carbon dioxide and hydrogen from renewable resources.
This patent application is currently assigned to SIEMENS AKTIENGESELLSCHAFT. Invention is credited to Bruce W. Rising.
Application Number | 20090289227 12/123515 |
Document ID | / |
Family ID | 41341401 |
Filed Date | 2009-11-26 |
United States Patent
Application |
20090289227 |
Kind Code |
A1 |
Rising; Bruce W. |
November 26, 2009 |
Production of Fuel Materials Utilizing Waste Carbon Dioxide and
Hydrogen from Renewable Resources
Abstract
The present invention is directed to a method for utilizing
CO.sub.2 waste comprising recovering carbon dioxide from an
industrial process that produces a waste stream comprising carbon
dioxide in an amount greater than an amount of carbon dioxide
present in starting materials for the industrial process. The
method further includes producing hydrogen using a renewable energy
resource and producing a hydrocarbon material utilizing the
produced hydrogen and the recovered carbon dioxide.
Inventors: |
Rising; Bruce W.; (Oviedo,
FL) |
Correspondence
Address: |
SIEMENS CORPORATION;INTELLECTUAL PROPERTY DEPARTMENT
170 WOOD AVENUE SOUTH
ISELIN
NJ
08830
US
|
Assignee: |
SIEMENS AKTIENGESELLSCHAFT
Munich
DE
|
Family ID: |
41341401 |
Appl. No.: |
12/123515 |
Filed: |
May 20, 2008 |
Current U.S.
Class: |
252/373 ;
204/242; 422/600; 423/418.2; 423/650; 477/30; 518/702; 518/704;
568/910 |
Current CPC
Class: |
Y02E 70/30 20130101;
Y02P 80/20 20151101; F05B 2220/61 20130101; B01D 2258/06 20130101;
B01D 53/73 20130101; Y02P 20/50 20151101; C07C 29/1518 20130101;
Y02P 90/50 20151101; C01B 2203/0261 20130101; Y02P 20/133 20151101;
Y10T 477/40 20150115; C01B 2203/061 20130101; Y02E 60/36 20130101;
B01D 53/1475 20130101; C01B 32/40 20170801; Y02C 20/40 20200801;
Y02E 10/72 20130101; C01B 2203/1241 20130101; Y02P 20/151 20151101;
C25B 1/00 20130101; F03D 9/19 20160501; C07C 29/1518 20130101; C07C
31/04 20130101 |
Class at
Publication: |
252/373 ;
518/702; 518/704; 423/650; 423/418.2; 568/910; 422/188; 204/242;
477/30 |
International
Class: |
C07C 27/06 20060101
C07C027/06; C01B 3/34 20060101 C01B003/34; C07C 1/04 20060101
C07C001/04; C01B 31/18 20060101 C01B031/18; B01J 19/00 20060101
B01J019/00; C25B 9/00 20060101 C25B009/00; F02C 7/36 20060101
F02C007/36 |
Claims
1. A method for utilizing CO.sub.2 waste comprising: recovering
carbon dioxide from an industrial process that produces a waste
stream comprising carbon dioxide in an amount greater than an
amount of carbon dioxide present in starting materials for the
industrial process; producing hydrogen using a renewable energy
resource; and producing a hydrocarbon material utilizing the
produced hydrogen and the recovered carbon dioxide.
2. The process of claim 1, wherein the producing hydrogen is done
by electrolysis of water using electricity generated from the
renewable energy resource, and wherein the renewable energy
resource comprises wind or solar energy.
3. The process of claim 1, wherein the producing hydrogen further
comprises producing oxygen as a by-product and using the oxygen in
a downstream process.
4. The process of claim 1, further comprising using electricity
produced from the renewable energy resource to reduce an amount of
carbon dioxide to a first amount of carbon monoxide and oxygen.
5. The process of claim 4, wherein the carbon monoxide and produced
hydrogren are converted to at least one of methane and methanol via
a catalytic process.
6. The process of claim 4, wherein the oxygen is utilized in the
gasification of a carbon feedstock to produce a second amount of
carbon monoxide, and wherein the second amount of carbon monoxide
is utilized in a downstream process.
7. The process of claim 6, wherein the carbon monoxide and produced
hydrogren are converted to at least one of methane and methanol via
a catalytic process.
8. The process of claim 1, wherein the waste stream comprises an
exhaust gas from a gas turbine engine.
9. The method of claim 1, wherein the produced hydrocarbon material
comprises methanol, and further comprising converting the methanol
to at least one of the group consisting of aromatic hydrocarbons,
olefins, and combinations thereof.
10. The method of claim 1, wherein the produced hydrogen is reacted
with carbon monoxide in the presence of the recovered carbon
dioxide to produce methanol.
11. The method of claim 1, wherein the produced hydrocarbon
material comprises methane, and further comprising converting the
methane to methanol.
12. The method of claim 1, wherein the produced hydrocarbon
material comprises methane, and wherein the methane is thereafter
converted into at least one of the group consisting of syngas, a
second hydrogen supply, carbon monoxide, and methanol.
13. The method of claim 12, wherein the methane is converted into
at least carbon monoxide and the second hydrogen supply, wherein
the carbon monoxide is directed for use in the production of
methanol, and wherein the methanol is produced by reacting the
carbon monoxide and at least one of the produced hydrogen from the
renewable energy resource and the second hydrogen supply in the
presence of the recovered carbon dioxide.
14. The methanol of claim 1, wherein the produced hydrocarbon
material comprises methane, and further comprising converting the
methane into at least one of the group consisting of syngas,
components of syngas, hydrogen, and carbon monoxide, and using the
hydrogen or carbon monoxide from the converting of methane, if
present, to produce methanol.
15. A system for utilizing waste CO.sub.2 comprising: an industrial
element for producing waste CO.sub.2; a second element powered by a
renewable energy resource for producing hydrogen; and a third
element utilizing the waste CO.sub.2 and the hydrogen for producing
a hydrocarbon material.
16. The system of claim 15, wherein the second element comprises an
electrolytic cell for the electrolysis of water for producing
hydrogen using electricity generated from the renewable energy
resource, and wherein the renewable energy resource comprises wind
or solar energy.
17. The system of claim 15, wherein the industrial element
comprises a gas turbine engine.
18. The system of claim 15, wherein the produced hydrocarbon
material comprises methanol, and further comprising a fourth
element for converting the methanol to at least one of the group
consisting of aromatic hydrocarbons, olefins, and combinations
thereof.
19. The system of claim 15, wherein the produced hydrocarbon
material is methane, and further comprising a fourth element for
converting the methane to methanol.
20. A system for recycling carbon dioxide, comprising: a first
plant configured to operate a process that produces a waste stream
comprising carbon dioxide in an amount greater than an amount of
carbon dioxide present in starting materials for the process; a
second plant that generates power from a renewable energy resource;
means for recovering the carbon dioxide from the waste stream;
means for producing hydrogen using the power from the renewable
energy resource; and means for producing a hydrocarbon material
utilizing the produced hydrogen and recovered carbon dioxide.
Description
FIELD OF THE INVENTION
[0001] The present invention relates to a method and system for
producing fuel materials from waste carbon dioxide using renewable
resources, and more particularly to a method and system for
producing fuel materials from carbon dioxide recovered from a waste
stream of an industrial process and hydrogen produced using
renewable energy resources.
BACKGROUND OF THE INVENTION
[0002] The need to control the world's greenhouse gases is a
principle focus of the world today. Greenhouse gases, i.e. carbon
dioxide, may be emitted into the atmosphere through natural
processes and human activities, such as the combustion of fossil
fuels (oil, natural gas, and coal), solid waste, trees and wood
products, and also as a result of other chemical reactions (e.g.,
manufacture of cement). Carbon dioxide is a particularly critical
greenhouse gas because it not only transmits visible light, but
strongly absorbs energy in the infrared wavelengths at which the
earth radiates energy to space. The absorbed energy may be
re-radiated to the earth, thereby warming the earth. Atmospheric
mixing ratios for carbon dioxide are now higher than at any time in
the last 800,000 years, standing at 383 parts per million (ppm)
compared to a pre-industrial revolution high of 280 ppm, although
this value may vary by location and time. Currently, carbon dioxide
emissions in the U.S. are at about 6 billion tons annually and 18
billion tons globally. Reducing carbon dioxide emissions from its
source is one primary aim of a number of global warming protocols,
however, substantial elimination of carbon dioxide production from
the vast majority of CO2 emission sources is not likely to be
realized.
BRIEF DESCRIPTION OF THE DRAWINGS
[0003] The invention is explained in the following description in
view of the drawings that show:
[0004] FIG. 1 is a flow schematic of a system for producing
methanol and/or hydrocarbon fuels from recovered carbon dioxide and
hydrogen produced from a renewable energy resource according to one
embodiment of the present invention;
[0005] FIG. 2 is a flow schematic of a system for producing
methanol and/or hydrocarbon fuels from recovered carbon dioxide and
hydrogen produced from a renewable energy resource according to
another embodiment of the present invention;
[0006] FIG. 3 is a flow schematic of a system for producing
methanol, from recovered carbon dioxide, carbon monoxide generated
by electrolysis, and hydrogen produced from a renewable energy
resource according to yet another embodiment of the present
invention;
[0007] FIG. 4 is a flow schematic of a system for producing
methanol from waste carbon dioxide, carbon monoxide, and hydrogen
produced from a renewable energy resource according to yet another
embodiment of the present invention;
[0008] FIG. 5 is a flow schematic of a system for producing carbon
dioxide, methane, methanol and/or hydrocarbon fuels from waste
carbon dioxide and hydrogen produced from a renewable energy
resource according to yet another embodiment of the present
invention; and
[0009] FIG. 6 is a flow schematic of a system for producing carbon
dioxide, methane, methanol and/or hydrocarbon fuels from waste
carbon dioxide and hydrogen produced from a renewable energy
resource according to still another embodiment of the present
invention.
DETAILED DESCRIPTION OF THE INVENTION
[0010] The inventors of the present invention have developed a
novel method and system for utilizing waste carbon dioxide for the
production of useful fuel materials. In one aspect of the present
invention, the present invention provides a novel, efficient, and
economical method and system for producing useful fuel materials,
i.e. methane, methanol carbon monoxide, syngas, gasoline products,
and/or other fuel materials, from carbon dioxide recovered from
carbon dioxide-containing waste streams via hydrogen produced by
renewable energy resources. In this way, the method and system of
the present invention are capable of utilizing waste carbon dioxide
to generate substantial amounts of useful fuel materials, as well
as reducing the amount of carbon dioxide transmitted into the
atmosphere and conserving conventional fossil fuels. As a result,
the typical problems, difficulties and expense associated with
carbon dioxide disposal may also be reduced or eliminated. Typical
carbon disposal costs include storage costs and the cost of
deep-well injection or other disposal techniques. In addition, the
present invention takes advantage of the remote locations of both
renewable energy power generation plants, i.e. wind farms, and
carbon dioxide producing industrial plants, such as power plants.
The close proximity of plants where hydrogen may be generated from
renewable energy resources and plants where carbon dioxide may be
captured from waste streams along with the use of materials
produced by each, reduces storage and transport costs in the
production of the valuable fuels according to the claimed
invention.
[0011] FIG. 1 depicts an embodiment of a system 10 for utilizing
waste carbon dioxide for the production of useful fuel materials in
accordance with the present invention. The system 10 includes a
plant, i.e. a wind farm 12, as is known in the art, for producing
energy from a renewable resource and a plant, i.e. an industrial
plant 14, which produces carbon dioxide as a waste product. The
wind farm 12 is typically located in a remote location, such as at
high altitudes, on plains, or away from population centers, where
wind speeds are likely to be relatively high and consistent on
average. In an embodiment, the wind farm 12 includes a plurality of
wind turbines 16, each of which converts the kinetic energy in wind
into mechanical energy. The mechanical energy is then converted to
electricity 18, which may be delivered to an electrical power
distribution grid 20 (storage of electricity on the grid 20 is an
option when such mechanisms are available). In one aspect of the
present invention, at least a portion of the electricity 18
generated by the wind turbines 16 is directed to hydrogen
generation 22 as indicted by arrow 24. The electricity 18 is
utilized for the production of hydrogen 26 and oxygen 28 from water
15, which is delivered to an electrolytic cell as shown by arrow 17
at hydrogen generation 22. The electrolysis takes place according
to the following electrolysis equation:
H.sub.2O+electricity.fwdarw.H.sub.2+1/2O.sub.2 (I)
[0012] Typically, known electrolysis processes require about 60
kW-hr of energy per kilogram of hydrogen produced by the
electrolysis of water. The produced hydrogen 26 may be used for the
production of useful fuel materials as set forth below. In
addition, per kilogram of the produced hydrogen 26, eight kilograms
of oxygen 28 are also produced. The produced oxygen 28 may be fed
to a storage facility 30 for storage and transport of the material
from the wind farm 12 as shown by arrow 32. As such, the
electrolysis reaction also provides a useful byproduct (oxygen 28)
that may be used in other industrial processes such as gasification
to product CO, the production of an oxy-fuel, and/or a process that
could potentially provide a source of carbon dioxide for any
reaction as set forth herein.
[0013] In an embodiment, the electricity 18 produced by the wind
turbines 16 may be used exclusively at hydrogen generation 22 for
the production of hydrogen and oxygen. Alternatively, the
electricity 18 produced by the wind farm 12 need not be utilized at
all or may be only partially used at hydrogen generation 22. In
this case, the electricity 18 is transferred to the grid 20 as
shown by arrow 34 for storage thereon along with or instead of the
transfer of the electricity 18 to hydrogen generation 22. Any
electricity 18 transferred to and stored on the electrical grid 20
may be sold or acquired as needed. Along with the grid 20, the
production of hydrogen 26 in hydrogen generation 18 may be
performed on a consistent basis using wholly or partially a
renewable energy resource. If the production of hydrogen is
required, and no wind is available at any point in time, the
electricity 18 produced by the wind farm 12 or other electricity
stored on the grid 20 from other sources may be transferred from
the grid 20 to hydrogen generation 22 to drive the electrolysis
reaction as shown by arrow 36.
[0014] It is contemplated that although a wind farm is discussed
herein, the wind farm 12 is merely exemplary of a renewable energy
resource. Alternatively, any other suitable renewable energy
resource may be used to produce power to drive the electrolysis
reaction for the production of hydrogen. Other exemplary renewable
energy resources include, but are not limited to sunlight,
hydroelectric, rain, waves, tides, and geothermal heat, each of
which may be naturally replenished.
[0015] In a next step, the hydrogen 26 produced from the wind farm
12 is combined with carbon dioxide. In an embodiment, the carbon
dioxide is recovered from a waste stream of an industrial process.
As is also shown in FIG. 1, the industrial plant 14 provides a
process, such as an industrial process, that forms a carbon
dioxide-containing waste stream 38. Numerous industrial processes
are known to produce mass amounts of carbon dioxide waste. In an
embodiment, the industrial plant 14 may be a power plant that
includes a plurality of gas turbine combustion engines for the
combustion of fuel, or any other heat engine with a carbon rich
fuel supply, i.e. a coal-fired power plant. Each of these
industrial plants produces a carbon dioxide-containing waste stream
comprising carbon dioxide in an amount greater than an amount of
carbon dioxide present in starting materials for the industrial
process. Further, other industrial processes such as calcining
operations, fuel decarbonization, and the like, produce relatively
large quantities of carbon dioxide waste.
[0016] Typically, either a portion of the exhaust gas or waste is
emptied into the atmosphere or various terrestrial and aquatic
methods are used for disposing the produced carbon
dioxide-containing products. The present invention provides a
method for utilizing the carbon dioxide that would otherwise be
emptied as waste into the atmosphere or would be required to be
stored or disposed of by methods that are expensive and require
storage size and space.
[0017] In an embodiment, the wind farm 12 and the power plant 14
are located in relatively close proximity to one another at a
remote location. In an embodiment, the wind farm 12 has been
optimized for the performance of the wind generation. In a
particular embodiment, the wind farm 12 and power plant 14, for
example, are located within 10 miles of one another. In this way,
the transportation costs for products, i.e. carbon dioxide, useful
in the production of fuel materials are kept at a minimum and are
readily available to produce the desired products at a central
location.
[0018] To utilize the carbon dioxide that would otherwise be
disposed of in an environmentally unfriendly and/or costly manner,
CO.sub.2 capture 40 recovers carbon dioxide 42 in the carbon
dioxide-containing waste stream 38. In an embodiment, the products
of a combustion process may, for example, be passed through a
condenser that condenses the majority of gases in the exhaust gas,
i.e. steam. The gases exiting the condenser may comprise carbon
dioxide and can be directed out of the condenser. The carbon
dioxide 42 may be converted into a liquid or a compressed gas and
may be recovered from CO.sub.2 capture 40 by any suitable method
known in the art.
[0019] In another embodiment, CO.sub.2 capture 40 may be carried
out using a conventional acid gas removal system based on aqueous
methanolamine (MEA), diethanolamine (DEA), methyldiethanolamine
(MDEA), and the like. In a particular embodiment, the CO.sub.2
recovery process is done by a Fluor Econamine Process. The Fluor
Econamine Process uses MEA coupled with proprietary stabilizer
additives, to recover CO.sub.2 from various combustion sources,
i.e. gas-fired systems. The process is widely used in the oil and
gas industry to condition natural gas by removing CO.sub.2 from
natural gas prior to injection of the processed gas for pipeline
delivery. Exemplary suppliers for CO.sub.2 recovery systems using
an amine process include UOP of Des Plaines, Ill., Shell Global
Solutions, and BASF. Typically, the CO.sub.2 recovery systems are
optimized to process high pressure gas streams found in refining
operations. Other solvents used to capture CO.sub.2 include the hot
potassium carbonate. Mitsubishi provides yet another embodiment of
solvent capture using a more complex amine, labeling their product
KS-1. Further numerous other processes for the recovery of carbon
dioxide are known, see e.g. Herzog et al, Annual Review of Energy
and the Environment, vol. 21: 145-166 (November 1996), Carbon
Dioxide Recovery and Disposal from Large Energy Systems, U.S.
Published Patent Application Nos. 20080072752, 20080060346, and
U.S. Pat. Nos. 6,838,071, and 4,810,266.
[0020] In an embodiment, at least a portion of the hydrogen 26 from
hydrogen generation 22 and the carbon dioxide 42 from CO.sub.2
capture 40 may be reacted to produce methanol as shown in FIG. 1
(or methane as shown in FIG. 5) according to any suitable process
known in the art. In a particular embodiment shown in FIG. 1, at
methanol production 44, at least a portion of the hydrogen 26 and
the carbon dioxide 42 are reacted to produce methanol 46 according
to the one of the following formulas:
CO.sub.2+2H.sub.2.fwdarw.CH.sub.3OH+1/2O.sub.2.DELTA.G=-4.1
Kcal/mole (II)
[0021] Reaction (II) is an electrochemical reaction and may require
electricity 18 to drive the reaction. In another embodiment, as
shown in FIG. 1, methanol 46 and water 48 are produced at methanol
production 44 according to the following equation.
CO.sub.2+3H.sub.2.fwdarw.CH.sub.3OH+H.sub.2O (III)
[0022] Reaction (III) is a well-known reaction in the art typically
carried out at 50-350 bar at 250-400.degree. C. over a catalyst,
such as a Cu/ZnO catalyst.
[0023] As shown in FIG. 5 and discussed in further detail below,
the hydrogen 26 and the carbon dioxide 42 may instead be reacted to
produce methane and water according to the following formula.
CO.sub.2+4H.sub.2.rarw..fwdarw.CH.sub.4+2H.sub.2O.DELTA.=-27
Kcal/mole
[0024] Generally, the production of methanol is a preferred route
because as a liquid it is more readily stored than gaseous
products, and methanol is an excellent starting material to produce
other chemical commodities (it could for example be a feedstock in
Haldor Topsoe's process to make gasoline from methanol). However,
the reaction can be tailored to produce either outcome.
[0025] The produced methanol 46 may thereafter be directed to a
suitable area for storage (not shown) or may be immediately
directed to a location for reaction with additional components for
the production of addition fuel materials. In one embodiment at
least a portion of the produced methanol 46 is further utilized to
produce useful hydrocarbon fuel materials. One particularly
suitable process for the conversion of the methanol 46 to a useful
fuel material is the well-known MTG (methanol to gasoline) process
by Exxon Mobil that converts methanol into highly aromatic gasoline
products U.S. Pat. Nos. 5,167,937 and 5,026,934 provide examples of
processes for the conversion of methanol to useful gasoline
products. Thus, in one embodiment, the methanol 46 is directed to
methanol conversion 50 as shown by arrow 49 where the methanol 46
is converted into gasoline products 52 using the MTG process as
shown by arrow 54. Alternatively, the methanol 46 may be utilized
in the production of biodiesel fuels or utilized in a methanol to
olefin (MTO) process as is known in the art for the conversion of
methanol into ethylene and propylene. Ethylene and propylene are
the two largest chemicals produced by the petrochemical industry.
The water 48 produced by the reaction of formula (II) may be
directed back to a suitable storage facility, utilized in another
process as described herein, such as syngas production 78, or may
be directed to other any suitable location.
[0026] In another embodiment, the recovered carbon dioxide 42 may
instead be completely or partially utilized to produce methanol by
another reaction that principally requires carbon monoxide, but
also requires the presence of the carbon dioxide 42 at methanol
production 44'. The reaction takes place according to the
formula.
CO+2H.sub.2.fwdarw.CH.sub.3OH (IV)
[0027] Reaction (IV) is a well-known reaction in the art typically
carried out at 50-350 bar at 250-400.degree. C. over a catalyst,
such as a Cu/ZnO catalyst.
[0028] As shown in FIG. 2, the hydrogen 26 from hydrogen generation
22 is combined with carbon monoxide 58 in the presence of the
carbon dioxide 42 from CO.sub.2 capture 40 to produce methanol 46'
at methanol production 44'. Alternatively, the hydrogen for the
reaction of formula (IV) may be provided in whole or in part from
hydrogen 84 from syngas production 78 as set forth below or from
any other suitable hydrogen source.
[0029] As shown in FIGS. 2-4, the carbon monoxide for the reaction
of formula (IV) may be provided from a gasification process
(gasification 57), the electrolysis of carbon dioxide (CO.sub.2
electrolysis 45), or from an independent carbon monoxide source (CO
source 62) as set forth below, or any other suitable source. As
shown in FIG. 2, in one embodiment, the carbon monoxide 58 is
provided for methanol production 44' by combining the oxygen 32
from hydrogen regeneration 22 (shown by delivered by arrow 56) with
a carbon feedstock 55 at gasification 57 according to the following
reaction to produce the carbon monoxide.
C+1/2O.sub.2.fwdarw.CO (V)
[0030] In general, nearly all carbon feedstocks have some moisture
or other inert/undesirable components. Thus, it is understood that
the product gases may not be limited to carbon monoxide as shown
above, but could include parallel reactions that produce carbon
dioxide, hydrogen, and possibly some water. In one embodiment, to
thus limit the number of undesirable products, the feedstock may be
delivered (pumped) as a dry product to primarily produce carbon
monoxide. A gasifier that is fed with a slurry (liquid, i.e. water,
+feedstock) typically has more carbon dioxide (i.e. 10% or so) than
one that is fed as a dry feed. Reaction conditions may vary
depending upon the feedstock composition, and are typically
adiabatic reactor conditions, i.e. 1300.degree. C. to 1,500.degree.
C. In another embodiment, however, other products may be formed.
For example, carbon monoxide and hydrogen may be produced from a
feedstock according to a gasification reaction as set forth in U.S.
Pat. No. 5,149,464. In another embodiment, the reaction includes
the catalytic partial oxidation of hydrocarbons that are liquid
under conditions of standard temperature and pressure to produce
hydrogen and carbon monoxide as set forth in U.S. Pat. No.
6,673,270, for example.
[0031] Suitable carbon feedstocks include petroleum coke, residual
or heavy oil, or other coal materials. Alternatively, the carbon
feedstocks may include material having a relatively high carbon
content (i.e. 85% or greater). The aim of using a carbon feedstock
is to capture the energy value of the low quality feedstock and
convert it to a gas stream that can then be converted to a range of
high quality products/commodities. In another embodiment, as shown
in FIG. 3, the electricity 18 provided at wind farm 12 is used for
the electrochemical reduction of the carbon dioxide 42 at CO.sub.2
electrolysis 45 according to the following formula to provide
another source of carbon monoxide 58'. The electrochemical reaction
may be performed in a suitable electrochemical cell.
CO.sub.2.fwdarw.CO+1/2O.sub.2 (VI)
The carbon dioxide 42 may be provided from CO.sub.2 capture 40 or
any other suitable source. The resulting carbon monoxide 58' (or
mixture of carbon monoxide and carbon dioxide) from CO.sub.2
electrolysis 45 may be utilized in the production of methanol 46'
at methanol production 44' according to formula (IV). Further, in
this embodiment, the oxygen 32' produced according to formula (VI)
may also optionally provide an oxygen supply for the reaction of
formula (V) at gasification 57 as shown in FIG. 2. In addition, the
highly pure oxygen 32 produced by hydrogen generation 22 and the
oxygen 32' produced by gasification 57 may be used in any other
known gasification technology to provide additional CO that can be
used to catalytically convert CO and H.sub.2 into chemical products
(i.e. methanol) pursuant to formulas (II) and (IV), for
example.
[0032] In yet another embodiment, as shown in FIG. 4, carbon
monoxide 58'' may be supplied for the reaction of formula (IV) from
any other suitable carbon monoxide source 62 remote from methanol
production 44', such as storage tanks or the like to supplement or
provide carbon monoxide for methanol production.
[0033] It is thus contemplated that the carbon monoxide for the
reaction of formula (IV) may come from any one, two, or three
sources described above. Typically, the carbon monoxide provided
(58, 58', and/or 58'') and the hydrogen 26 are reacted on a
catalyst, such as a mixture of copper, zinc oxide, and alumina in
the presence of added carbon dioxide. The reaction may take place
at 5-10 MPa (50-100 atm) and at a temperature of about 250.degree.
C. to produce the methanol 46' with high selectivity. The produced
methanol 46, may be used for any suitable purpose or may be used to
produce gasoline products 52 as described above according to the
MTG process.
[0034] In another embodiment, as shown in FIG. 5, the recovered
carbon dioxide 42 from carbon dioxide capture 40 and the hydrogen
24 from hydrogen generation 22 may be reacted according to the
Sabatier process as is known in the art at methane production 64.
The resulting products are methane 66, which may be converted to
one or more usable hydrocarbon compounds, and water 68, which may
be used for any suitable purpose. The Sabatier reaction takes place
according to the formula:
CO.sub.2+4H.sub.2.rarw..fwdarw.CH.sub.4+2H.sub.2O.DELTA.=-27
Kcal/mole (VII)
[0035] The reaction typically takes place at elevated temperatures
in the presence of a nickel catalyst. Typically, the reaction takes
place at a maximum temperature of about 300.degree. C., although
the catalyst selection can reduce the process conditions closer to
ambient. U.S. Pat. No. 4,847,231 describes the use of catalysts,
i.e. ruthenium, to produce gas phase methane from hydrogen and
carbon dixiode, for example. In one embodiment, the produced
methane 66 is directed to methanol production 70 as shown by arrow
72 for the conversion of the methane 66 to methanol 74 according to
any suitable process for converting methane to methanol known in
the art. Currently, approximately 90% of the world's methanol is
manufactured from methane. The process is typically accompanied by
the partial oxidation of the methane to CO and H.sub.2, and then
reaction of over a copper catalyst to generate methanol. Currently,
the process is available from Haldor Topsoe A/S, Lyngby, Denmark or
Davy Process Technology, London, UK. The produced methanol 74 may
be directed to methanol conversion 50 as shown by arrow 76 to
produce useful gasoline products 52, such as via the MTG process.
In another embodiment, the methane 66 is directed to syngas
production 78 as shown by arrow 80 and is converted to carbon
monoxide 82, hydrogen 84, and/or syngas 86 (a mixture of CO and
H.sub.2) according to the following reaction.
CH.sub.4+H.sub.2O.fwdarw.CO+3H.sub.2 (VIII)
[0036] As set forth in U.S. Pat. No. 6,293,979, the above reaction
converting methane to syngas nickel may take place over catalysts,
particularly nickel (with or without other elements) supported on
alumina or other refractory materials. See Kirk and Othmer,
Encyclopedia of Chemical Technology, 3rd Ed., 1990, vol. 12, p.
951; Ullmann's Encyclopedia of Industrial Chemistry, 5th Ed., 1989,
vol. A12, pp. 186 and 202; U.S. Pat. Nos. 2,942,958, 4,877,550,
4,888,131, EP 0 084 273 A2; EP 0 303 438 A2; and Dissanayske et
al., Journal of Catalysis, vol. 132, p. 117 (1991).
[0037] The resulting carbon monoxide 82, hydrogen 84, and syngas 86
may be utilized as desired. For example, the carbon monoxide 82 and
the hydrogen 84 may be directed to methanol production 44' as shown
by arrow 85 and utilized to produce methanol according to formula
(III) above with or without carbon monoxide 58 provided from the
carbon monoxide source 62. In addition, the produced hydrogen 84
may be utilized to supplement the hydrogen 26 produced by hydrogen
generation 22 as shown by arrow 88 in FIG. 3. Further, either the
hydrogen 26 produced by hydrogen generation 22 and the hydrogen 84
from syngas production 78 may be utilized for the production of
methanol 44' as set forth in formula (IV).
[0038] In another embodiment, as shown in FIG. 6, at carbon
monoxide and methane production 90, the hydrogen 26 and the
recovered carbon dioxide 42 may be utilized in a modified Sabatier
process in combination with a reverse water gas-shift reaction to
produce methane 92, carbon monoxide 94, and water 96 according to
the formula:
3CO.sub.2+6H.sub.2.fwdarw.CH.sub.4+2CO+4H.sub.2O (IX)
[0039] For the above reaction, temperatures may range from about
180.degree. C. to about 200.degree. C. and pressures may range from
about 50 to about 100 bar over a catalyst. It is contemplated that
these values may be higher or lower depending upon the choice of
catalyst for the reaction. The hydrogen for the above reaction may
also be provided from a downstream process, such as syngas
production 78, as discussed below.
[0040] The produced methane 92 may be utilized to produce methanol
74 at methanol production 70 and/or converted to syngas and its
components, carbon monoxide 82 and hydrogen 84, at syngas
production 78. Once the methane 92 is converted to methanol 74 at
methanol production 70, the methanol 74 may thereafter be converted
to into useful gasoline products 52 at methanol conversion 50 using
the MTG process as set forth above. The produced carbon monoxide 94
may be directed to methanol production 44' as shown by arrow 98.
Further, the methane 92 may optionally be directed to syngas
production 78 and/or methanol production 70. If the methane 92 is
directed to syngas production 78, the produced carbon monoxide 82
may be directed to and utilized at methanol production 44'. The
amount of produced carbon monoxide 82, 94 may be sufficient to form
methanol 46' at methanol production 44' or may supplement the
carbon monoxide 58, 58', 58, supplied from other sources.
Similarly, the produced hydrogen 84 may be utilized to partially or
completely supplement the hydrogen 26 produced by hydrogen
generation 22 as shown by arrow 88 for any process described
herein. For example, the produced hydrogen 84 may be utilized at
methanol production 44' as shown by arrow 87 in lieu of or along
with the hydrogen 26 from hydrogen generation 22 (shown by arrow
89), Carbon dioxide for methanol production 44' may be provided
from CO.sub.2 recovery 40 as shown by arrow 91.
[0041] As described above, the present invention provides a
relatively inexpensive and optimized system and method for
producing useful fuel products from hydrogen generated from
renewable energy resources and carbon dioxide provided in waste
streams of industrial processes. According to one aspect of the
present invention, the carbon dioxide from the waste streams of
industrial processes are useful to provide reactants for the
production of a number of different fuel materials or are useful as
fuel materials themselves. Additionally, instead of being required
to dispose of the carbon dioxide from waste streams by costly
methods such as deep well injection, the carbon dioxide in the
present invention may be utilized to provide sources of methane,
methanol, syngas, carbon monoxide, hydrogen, and other hydrocarbon
fuel materials, i.e. straight-chain and aromatic hydrocarbons and
olefins. In addition, by reacting the carbon dioxide with other
compounds, the carbon dioxide may be provided in chemical forms
more suitable for storage and transport.
[0042] While various embodiments of the present invention have been
shown and described herein, it will be obvious that such
embodiments are provided by way of example only. Numerous
variations, changes and substitutions may be made without departing
from the invention herein, Accordingly, it is intended that the
invention be limited only by the spirit and scope of the appended
claims.
* * * * *